Overview of Intelligence
© Kim Taylor, September 2007
Psychologists today tend to define “intelligence” as “what intelligence tests
measure”. That is, it’s not a commodity that can be precisely measured or
quantified.
Intelligence can be thought of as the ability to think abstractly; this definition,
however, still fails to reflect or encompass all relevant and related skills, mental
abilities and cognitive processes.
What abilities do you think are a part of what we know as “intelligence”?
IQ
A person’s IQ or Intelligence Quotient is determined by a mathematical formula:
IQ = Mental Age (MA) / Chronological Age (CA) x 100
Using this formula, what would be your guess about the IQ score that represents
“average” intelligence?
Would a 6-year old child with a mental age of 8 be considered as having an
above average or below average IQ?
How about a 12-year old with the mental age of 10-year old?
Commonly Used IQ Tests
Stanford-Binet (children)
Weschler Adult Intelligence Scale (WAIS) or WAIS-R (revised version)
Weschler Intelligence Test for Children (WISC)
Each of these tests is really a series of sub-tests, not one “exam” as you might
think.
The WAIS, for example, groups its subtests by aptitudes rather than age. The
Verbal subtests include:
Information – knowledge such as “Who was Shakespeare?”
Comprehension – “Why do we have zip codes?”
Arithmetic – story problems
Similarities – “How are good and bad alike?”
Digit Span – repeating a series of numbers forward and backward
Vocabulary – definitions
The Performance sub-tests include:
Digit Symbol – learning and drawing figures that seem meaningless
Picture Comprehension – identifying what’s missing
Block Design – using colored blocks to replicate geometric designs
Picture Arrangement – arranging cartoons into a story sequence
Object Assembly – using puzzle pieces to form some meaningful object
Use of IQ Tests
IQ tests are used today by the military, legal system, and educational settings.
What are the advantages and disadvantages of individual vs. group intelligence
testing?
A Few Terms to Understand and Questions to Consider
Standardization procedures – uniform and consistent procedures used for
administration and scoring of an intelligence test (consider term “standardized
test”)
Why are these important to have in place?
Norm – average performance of a particular group based on a bell curve with
standard deviation and measures of central tendency (consider term “norming”)
What is a bell curve and what does it represent?
What is a standard deviation?
What are measures of central tendency?
Why is norming important?
(Test) Reliability – think repeatability – a reliable test will yield the same score
every time the individual takes it
(Test) Validity – a valid test will measure what it’s supposed to measure – that is,
a valid intelligence test will measure intelligence, not education
What’s the difference between intelligence and education?
Why are validity and reliability important?
Aptitude Test vs. Achievement Test
What’s the difference between them? Consider the Scholastic Aptitude
Test (SAT)?
When is it taken and why?
Would your Psychology final exam be considered an aptitude test or an
achievement test? Why?
Theories of Intelligence
Psychologists love theories. As with any other topic in psychology, there are
many theories of intelligence.
There are Factoral theories – theories that address the structure of intelligence –
and Process theories – theories that address how we problem solve and interact
with the environment.
Factoral Theories:
Spearman’s Two-Factor Theory - Intelligence consists of G-factor (general
intelligence/genetics) and S-factor (specific abilities)
Thurstone’s Primary Mental Abilities - Intelligence is a composite of seven
primary mental abilities:
Verbal comprehension – understanding of meanings & ideas
Numerical ability – ability to perform quick number computations
Spatial relations – ability to visualize & manipulate forms in space
Perceptual speed – ability to grasp perceptual ideas quickly and to
determine similarities & differences
Word fluency – ability to use words quickly & fluently in rhyming,
anagrams, crosswords
Memory – recalling of lists, formulas & definitions
Inductive reasoning – ability to derive general rules & principles from
information given
Guildford’s Structure of Intellect – There exists no overall intelligence factor;
however there are over 150 separate abilities classified into three major
intelligence functions:
Mental operations – how we think
Content upon which operations are performed – what we think about
Products of applying operation to content – what do we do with it
Process Theories:
Sternberg’s Information-Processing Approach – There are 6 steps of “practical
intelligence”:
1. Encoding – identifying key terms/concepts and retrieving information
relevant from LTM
2. Inferring – determining the nature of relationships
3. Mapping – clarifying relationships between past & present situations
4. Application - deciding if information about known relationships can be
applied to a present problem
5. Justification – deciding if the answer can be justified
6. Response – providing the best answer based on proper information
processing at each of the previous stages
Note: Good problem solvers tend to perform better on intelligence tests as
they spend more time analyzing the question, particularly in the encoding
stage.
Gardner’s Theory of Multiple Intelligences – There are seven types of
intelligence, all unique and independent of one another:
Linguistic
Logical – mathematic
Spatial
Musical
Body kinesthetic
Interpersonal
Intrapersonal
What characteristics or occupations do you think would correspond to
individuals high in each of the above areas of intelligence?
In which areas above do you believe you would score highest? Lowest?
A Few Other Thoughts
It is likely that biases in intelligence tests are inherent and perhaps unavoidable.
Why might this be true?
Do you agree or disagree? Why or why not?
As with most other human characteristics, intelligence is likely a result of the
interaction between nature and nurture.
Explain this statement, providing examples to support your thoughts.
There is some evidence that suggests that an enriched and stimulating
environment can have a positive impact on intelligence.
What are your thoughts about this?